Given $C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O : \Delta H = -72 \ \text{kcal}$,calculate the energy required for the formation of $1.6 \ \text{g}$ of glucose.

If $10 \ g$ ($90 \%$ pure) limestone is heated,what volume of $CO_2$ in liters will be obtained at $NTP$?

What amount of conc. $H_2SO_4$ solution should be used to prepare $500 \ mL$ of $0.5 \ M \ H_2SO_4$ (in $g$)? (The concentration of $H_2SO_4$ solution being used is $90\%$ and molecular mass of $H_2SO_4 = 98.079 \ g \ mol^{-1}$)

Based on the reaction $CH_4 + 2O_2 \to CO_2 + 2H_2O$,calculate the number of moles of oxygen required to react with $4.8 \, g$ of methane.

If the density of $1 \ mol$ of a gas at $NTP$ is $0.1784 \ g/L$,what is the weight of $1 \ mol$ of the gas in $g$?

The mass of a mixture containing $NaCl$ and $NaBr$ is $4.0 \ g$. If $Na$ is $30 \%$ of the total mixture,the composition of $NaCl$ in the mixture is (in $\%$)